VSTS testing framework

I have recently received an inquiry from a client that wants to migrate his NUnit test to VSTS. They had heard that VSTS unit tests performed worse than NUnit.

My answer (some info comes from MSFT)

• It is true that running a set of empty tests unsing NUnit is faster than running them using VSTS (about 20% faster), but if these tests are not empty and have something in them, then this difference reduces.

• Performance using VSTS will be best if you run the test from the command line and using the /noisolation option (MSTest.exe) [When VSTS tests are executed on the IDE, each one runs on its own process, so that if a test crashes, the whole environment does not crash too. Obviously, there is a performance tradeoff. You can avoid this tradeoff by running them on the command line and specifying "no isolation".]

• They are working on performance for the next version and doing good progress.
  

I have also found a couple of old (beta) bugs regarding unit testing and performance but these should be ok in the RTM vesion that you have:

• Editing unit tests is slow (Open but beta issue)
• Unit tests take too much time (CLOSED - Beta issue)
  

There is also an open bug on web testing eating too many resources (but I don't think you have this kind of tests)

• Web Test eat all resources (OPEN)